Lea and Kairi were prepared for another day of practice. They summoned their Keyblades before meeting Merlin at their usual training spot.

"You can go ahead and put those Keyblades away, children. Today we have something else to focus on. Your education. I'd be remiss in my duties as your teacher if I only focused on your combat training. Learning and sharpening the mind—why, those are just as important as fighting."

"Sooo, its like we're back in school..." Lea complained, but he didn't seem too upset by the idea.

"Precisely," Merlin replied, smiling. He took a sip of his tea.

"What are we going to be learning about, Merlin?" Kairi asked as she dismissed her Keyblade.

"Do you know the history of the ancient Keyblade War?"

"Master Yen Sid mentioned it briefly, but he didn't fully explain it to me, no."

"And you, lad?"

Lea shook his head. "Nope." None of this stuff makes any damn sense to me.

"Ah. You see, this is unacceptable. One cannot properly prepare for the future unless they are knowledgeable about the past. If one does not know history, they are doomed to repeat it." Merlin pensively stroked his beard. "Of course, in Xehanort's case, it may have been the opposite. Very few know of the ancient Keyblade War. Xehanort was one of them. And he used that knowledge to try and recreate one."

Lea couldn't resist asking. "I can't deny that I'm curious. What exactly is the deal with this Keyblade War stuff?"

"Well, that's what I'm here to teach you. Ahem. Long ago, in the age of fairy tales, the World was filled with light—a gift, many believed, from an unseen power known as 'Kingdom Hearts'. You see, Kingdom Hearts was protected by its counterpart, the 'χ-blade', so that none could ever lay hands on its mysteries."

Merlin waved his wand and summoned an image of the letter 'χ' in the air for Lea and Kairi to see.

"The letter you see before you is 'χ'. It is pronounced 'Chi', like the word 'Keyblade'. Some call it 'Kye'. This 'χ-blade'—you could call it the true Keyblade. This is what Master Xehanort is after. He wants to unlock the true Kingdom Hearts. A feat that no one has ever accomplished before."

Lea stared at the letter 'χ' that Merlin summoned. That letter. That's what Xehanort called Isa. It's the same shape as his scar. He wanted to use Isa to create the χ-blade. That's what his goal was all along.

"Are you paying attention, Lea?"

"Oh, uh, yeah. 'Course I am!"

"Good. Now, Kingdom Hearts was seen as the origin of all light in the World. But in time, the World was overrun by legions who wanted the light all for themselves, and the first shadows were cast upon the land. These warriors crafted 'Keyblades' in the image of the original χ-blade, and waged a great war over Kingdom Hearts. We call this the 'Keyblade War'."

The Keyblade War. It almost destroyed the World. Kairi was listening very carefully to everything Merlin said. The subject interested her a great deal.

"But though the war extinguished all light from the World, the darkness could not reach the brightness inside every child's heart. With that light, the World was remade as we know it today, with countless smaller worlds shining like stars in the sky."

So. Children were the key to rebuilding the worlds, huh? Lea smiled at the thought.

"As for the real χ-blade, it did not survive the battle. The two elements that created it, one of darkness and one of light, shattered into twenty pieces—seven of light; thirteen of darkness. That is what Xehanort is after. He wants to pit thirteen Seekers of Darkness against seven Guardians of Light. He needed thirteen empty vessels to place his heart into, so he could begin another Keyblade War."

Empty vessels. That's all Xehanort was after. That's why he conducted the experiments. Isa. He's just an empty husk to Xehanort, not a person. His soul, his mind...his heart. None of that matters to him. Isa's been turned into a hollowed-out shell to house darkness. That's why Saïx's personality changed so much. He was never really Isa. The whole time, he was just another Xehanort masquerading as him. A puppet.

Lea remembered the moment he arrived in the Sleeping World to rescue Sora.

"Promises to keep. I'll always be there to get my friends back. What, bad timing? You had your perfect little script, but you kinda forgot to write the sequel. Now, let's find out what happens!"

That's why the old man sent Isa to attack me. He was rubbing it in my face. I'm sure Xemnas knew the whole time, too. I thought I was plotting behind his back, but he was two steps ahead of me the entire time. Lea tried his best to mask the disgust he was feeling at that moment.

Merlin continued the lesson. "And as for the source of all light—the one true Kingdom Hearts—it was swallowed by the darkness, never to be seen again. As long as it remains there, even the brightest world will have its dark corners. After all, light begets darkness, and darkness is drawn to light. For this reason, some decided to use the Keyblade—a weapon designed to conquer the light—to defend the light instead. These were the first heroes of the Keyblade. And you are the inheritors of that legacy."

After the day's history lesson, Kairi and Lea went to their usual spot.

Lea was looking out over the horizon, lost in thought. So. Isa's a Seeker of Darkness. And I'm a Guardian of Light. If darkness if drawn to light, then...I'll be his light.

He turned his attention to the sunset, its red light shining down upon the land. His red hair glistened in the sunlight.

Red. It's the color of light that travels the farthest. That's why the sunset is red. Light is made up of lots of colors. Seven colors of light. Seven Guardians of Light. In that case, I'll be the red light. No matter how far away Isa is, I'll be able to reach him. And I'll bring him back.

Lea looked over at Kairi and noticed that she seemed lost in thought, too. She was unusually quiet today. "Got something on you mind, Kairi?"

"Well, it's strange. I've actually heard about the Keyblade War before."

"You have?"

She nodded. "Yeah. It was a story my grandmother used to tell me, when I was really little. Back when I still lived in Radiant Garden."

She remembered when Sora changed back after becoming a Heartless. They were both in Traverse Town in the underground cavern. The painting of the sun began to shine. Then, suddenly, it changed into a crescent moon.

"A light at the end of the tunnel..."

"Oh, your grandma's story, right?"

"That's right. We were together."

"You know what's funny? I looked everywhere for you, but you were with me all along. Finally, we're together, Kairi."

Kairi smiled. "I thought it was just a fairy tale. But, I guess it really wasn't."

"So, what was the story your grandma told you?"

Kairi closed her eyes and placed her hand over her heart. In her mind, she could hear the words of her grandmother so clearly. Kairi begged her to tell that story so many times. She was able to repeat it verbatim:

"Long ago, people lived in peace, bathed in the warmth of light. Everyone loved the light. Then people began to fight over it. They wanted to keep it for themselves. And darkness was born in their hearts. The darkness spread, swallowing the light and many people's hearts. It covered everything, and the world disappeared. But small fragments of light survived, in the hearts of children. With these fragments of light, children rebuilt the lost world. It's the world we live in now. But the true light sleeps, deep within the darkness. That's why the worlds are still scattered, divided from each other. But someday, a door to the innermost darkness will open, and the true light will return. So, listen, child. Even in the deepest darkness, there will always be a light to guide you. Believe in the light, and the darkness will never defeat you. Your heart will shine with its power and push the darkness away."

"Huh. It does sound really similar to what Merlin said."

"Yeah. You know...I..."

"Hm? What?"

"I remember my grandma told me that story when I was inside the castle."

"The castle, huh?"

Kairi nodded and was silent for a moment. "You know, Lea. I think...I do have other memories of being inside the castle. I wish I could remember more clearly. But...I remember...being surrounded in darkness. I think...I was locked up."

I wonder if she's talking about the experiments... "So, you remember being kept prisoner by Xehanort?"

"I don't know... Maybe. I'm not really sure." She said as she shook her head. "I just know that the story of the Keyblade War—hearing it brought back some memories." Kairi looked like she was struggling really hard to recall something.

Lea looked at her with concern. Maybe...she's starting to remember her time being experimented on by Xehanort. I'm not sure she'd really want to have those kinds of memories, though.


"Okay, Isa. Today your job is just delivering some letters."

Isa was barely listening. He had an awful nightmare last night. He couldn't really remember what it was about. All he remembered was a great darkness coming down from the sky. Then, he saw a large crossroads with a heart-shaped moon in the sky. It felt so ominous. Almost like a graveyard. He couldn't shake he feeling that something very bad was on the horizon.

Lea noticed that he seemed a bit spacey. "Are you sure you're okay?"

"Oh. Yeah. I'm fine."

"I can come with you today, if you want."

"No. It's okay. I can do it."

"You sure?"

Isa smiled a bit. "You worry too much." Lea always looks out for me.

Isa and Lea went their separate ways and did their odd jobs. After a few hours, Isa decided to take a short break. He made his way over to the park in Sunset Terrace. There was a small fountain in a secluded little area.

I'm kind of tired today. Isa took a moment to look at his reflection in the fountain. It looked strange. Like a dark shadowy figure. He jolted backward, startled.

The shadowy reflection then appeared to reach its hand out. Isa stared at it until it began walking towards him.

"Ah! Stay back!" He instinctively guarded himself with his arms while walking backwards.

The dark figure was completely black with round yellow eyes. It walked straight through him. In that moment, Isa felt everything going hazy. The next thing he remembered was waking up to Lea's voice calling his name while he was lying on the ground.

"Isa!"

Isa opened his eyes. Lea was kneeling beside him.

"Here you are. I've been looking everywhere for you. You really had me worried." Lea said as he helped Isa to his feet.

"I'm really sorry. I don't know what happened."

"...Listen. Are you sure you're okay?"

I was probably just seeing things. "Yeah."

Lea noticed he sounded a bit depressed. "C'mon. Let's go sit down."

The pair made their way to Sunset Hill and sat down on the bench. It was dark out. The moon hanging in the sky was a thin crescent sliver. It was the final phase of the moon. Tomorrow, the moon would be totally shrouded in darkness. It wouldn't reflect the sun's light. It would be invisible in the sky. It was the same symbol as the one on Isa's jacket.

Isa was staring at the moon when Lea decided to voice his concerns. "Hey. Um. I'm not trying to coddle you or anything. But I think it's probably better if I came with you from now on."

"No. It's okay. You're not coddling me." He didn't put up as much resistance as Lea expected.

"Oh...okay." Maybe he's been having flashbacks lately. Lea tried to change the subject to something more lighthearted. "Tomorrow, we should have enough munny. Then, next week is the festival. We can finally go to the beach."

Isa smiled sadly. "Yeah. It's going to be so much fun."

"Well, c'mon. Let's get outta here and go home."

Lea and Isa stood up to leave.

Suddenly, out of nowhere, a black portal materialized right in front of them. Out of the portal stepped a man in a black coat with his hood up. "So. This is where you've scurried off to, X." The man looked around. "Such a tiny little world. A prison."

"Who are you!?"

The black-robed man simply ignored Lea and continued to address Isa. "You've been able to feel it, haven't you? Your time is almost at its end. Soon, your heart will be completely swallowed by the darkness within you. There is no escaping that fate." His face could not be seen under his dark hood.

Both boys were rooted to the spot and couldn't move. All of Isa's bad feelings from the day were now coming true.

Just then, another man wearing a familiar eyepatch walked out of the dark portal. "Now that he's been banished, it's time to take you back with us."

Isa's eyes widened in terror upon seeing this man.

"Braig!" Lea shouted.

"Now how in the world did you get here, Red?" He laughed heartily.

"H-how did you know where to find us!?"

"Easy." Xigbar pointed at Isa. When he smiled, there was a mean glint in his golden eye. "Him."

The robed man finally took off his hood.

Who is he!? He's got the same white hair as that other apprentice guy. But he looks different, Lea thought.

The white-haired man spoke. "That scar you have. It lets us know where you are at all times. There's nowhere for you to run or hide. You are one of the chosen. You belong to us."

Lea ran in front of Isa who was frozen in shock. He felt a sense of panic overcome him. "You're crazy if you think I'll just stand by and let you take him!"

"Oho, so cute. Kid thinks he's a hero," Braig teased.

Without warning, the white-haired man quickly dashed behind Lea and knocked him out using an unusual weapon.

"Lea!" Isa shouted. But before he could do anything else, he was knocked out as well.

Isa woke up to find himself in an unfamiliar place. It was a dark laboratory-like area actually located in the basement of the mansion in the woods. He saw Lea lying on the ground not far from him. "Lea!"

"Ah-ah-ah. Don't move." Braig lifted one of his arrowguns and pointed it at Lea.

Isa felt himself trembling with anger. "Leave him alone!"

"Ooooh. So, it looks like this one does have a bit of that fighting spirit, after all. Who'da guessed?"

Isa gave Braig an icy glare.

"Do you always have to glare at me like that?"

The white-haired man, who was really Young Xehanort, thought back to the world he had previously visited, not that long ago. It was a world from the future. That world with the toys. Thanks to my experiments there, I learned it's possible to plant a heart into the vessel of our choosing. Even an empty puppet can be given a strong heart. He looked directly at Isa. "It seems the empty puppet has come back to life. It must have been because of this boy."

"He's not a puppet."

Young Xehanort took a step towards Lea. "I see you're finally awake." He summoned a strange black-and-white weapon with a clock and a goat's head on it.

"Stop! Don't hurt him! You can take me back with you if you want! Just leave Lea alone!"

Braig found Isa's pleading quite amusing. "You two are quite the pals, aint ya? Aww. You're making me all warm and fuzzy inside."

He's willing to sacrifice himself for this boy. I see. So, that's what makes his heart so special. "You truly are a remarkable specimen."

Isa said nothing to Young Xehanort.

"Our experiments creating Heartless were attempts to control the mind, and convince it to renounce its sense of self. When people experience extreme pain, they will disassociate from their body and their reality in order to get relief. At the moment of disassociation, their mind will become fragmented. In the end, the experiments proved to be a failure. All the subjects hearts' collapsed, even those of the most stalwart. All except for you."

Isa looked on, unable to react.

"Thanks to you, we have learned of the heart's folly."

The heart's folly?

"The heart that loves another even more than oneself cannot collapse. The power of the human heart is indeed vast. But. That same power is the heart's very own weakness." He looked at Lea. "That which we treasure has power over us. The heart is captive to it. And that makes it its weakness. For you see, the heart that loves is far more susceptible...to pain."

Young Xehanort remembered the pain of the toys after they were separated from Andy. It allowed Buzz to be consumed in darkness and lose his sense of self. He forgot who he was and attacked his friends.

"What do you want with my friend?"

"Look...Such tremendous darkness. All because he was ripped away from the boy who cares about him most."

He approached Lea, weapon in hand.

"No! Stop it! Get away from him!" yelled Isa.

"Your weakness is quite clear. I will take from you that which you cherish most. The heart of your friend. Then your mind will no longer put up any more resistance."

"No! Lea!" Isa began to cry.

Young Xehanort gave Isa a sideways glance. "Recusant. You will not be waking up this time."

The last thing Isa recalled was watching the white-haired man draw his blade and point it at Lea.

"NOOO!"

Isa couldn't hear anything. Not even his own voice screaming. His mind became consumed in total blackness. All was dark and still. The only thing he was aware of was his own inner thoughts.

I just want to protect Lea. But I'm not strong enough. I'm too weak to save him. Too weak. To save him, I need to become stronger. I need more power. More power. More...power...

...More... ...Power...

...Power...

In a split second second, Isa became like a feral animal. He lunged at Young Xehanort and knocked him down.

"What!?"

Just like that, they were engaged in combat.

Braig shot a few rounds, but it barely did anything to stop him. "What's goin' on!?"

"It seems his fear has sharpened into rage. He has awakened the darkness inside of him." Young Xehanort smiled.

All of Isa's hair stood on end. His face became red. The scar on his forehead swelled until it looked twice as large as it normally did. He was like a beast. He attacked with his bare hands, like claws. His eyes were glowing yellow, like a Heartless.

"So, what do we do now?"

"This boy is the fire that fuels his anger. By the time we return, he'll probably have finished off his friend already. I'm sure he'll be far easier to control by then."

With that said, both Young Xehanort and Braig disappeared into a dark corridor, leaving Lea alone with the berserk Isa.

"Isa!" Lea shouted as he ran toward his friend. But once he got closer, he stopped short.

An ominous feeling filled the air around Isa. He was emanating a frightening energy. He stared blankly, as if he was in some kind of daze.

Lea slowly took another step forward toward his friend. "Isa?"

But as soon as he made a move, Isa lunged at him.

"Wh-What? Isa, stop!"

Isa had strength that Lea had never seen from him before. He wasn't acting like himself at all. Isa would never attack me. It's like something is possessing him.

Isa continued to attack Lea seemingly without any awareness of what he was doing. He was frighteningly strong.

"Isa, snap out of it!" Lea yelled, but it didn't seem like Isa could hear him. Lea was having a hard time protecting himself from Isa's vicious blows, but he was reluctant to use too much force to fend him off.

Damn it! What do I do!? I don't want to hurt him! But if I don't do something, he's going to kill me!

Lea took quite a beating as he pondered over what to do. His arms and legs were black and blue.

"Arrrghhh!" he shouted as he was thrown against the wall.

Isa came charging right at him as he was backed against the wall.

Lea instinctively shielded himself with his arms while yelling at the top of his lungs. "Isa! STOOOOP!"

Surprisingly, that worked. Isa stopped attacking Lea. He just stood there, motionless.

Lea slowly got up and approached him. He placed his hands on his shoulders and spoke gently. "Isa. It's me. Lea. Can you hear me?"

Isa shut his eyes tightly. "Urgh." The scar on his brow was contorted with pain.

When he opened his eyes, they were no longer glowing bright yellow, like a Heartless. They were the same gold color from before. He was panting and covered in sweat. "Lea...?"

"Are you all right!?" Lea asked frantically.

"I think so..." Isa said, looking down at the ground. "Wait! What happened to those guys!?"

"They're gone. You chased them away. You saved me." Lea still had his hands on Isa's shoulders.

"I did?"

"Yeah. Then you went totally berserk. You...don't remember?"

"No..." Isa looked at Lea and noticed the bruises he had all over. "Was I...the one who did that to you?"

Lea was reluctant to answer him. Of course, he didn't want to lie, either. He turned his head to hide his troubled expression, saying nothing.

So, it's true...I attacked Lea. The darkness inside me took over. What if that happens again? Suddenly, he became very afraid.

"C'mon. Let's hurry up and get outta here, okay?"

"...Yeah..." Isa was still a bit disoriented after everything that happened. Lea took him by the hand and they both left the mansion.